Answer
Under the Continuous Survey of Machinery (CMS) scheme, Classification Societies (such as IRS, LR, DNV, and ClassNK) allow a qualified Chief Engineer to open up and inspect specific machinery items to distribute the 5-year special survey workload.
However, there is a strict regulatory boundary. The following list details what the Chief Engineer CANNOT inspect or credit under CMS; these items must be physically examined and certified exclusively by an attending Class Surveyor.
1. Main Propulsion and Power Transmission
Main Engine Crankshaft & Internal Line: The crankshaft, main journals and bearings, crankpin bearings, and crankpin bolts are strictly excluded.
Main Reduction Gearing: The complete main reduction/increase gear assembly, flexible couplings, and clutches.
Propulsion Shafting: Tailshafts, intermediate shafts, sternbushes, and stern tube seals.
The Propeller Assembly: The complete propeller unit (including Controllable Pitch Propeller mechanisms).
Turbines: Complete main steam or gas turbine propulsion units.
2. Boilers and High-Pressure Plant
Boilers: Main boilers, auxiliary boilers, and exhaust gas economizers.
Main Pressure Vessels: High-pressure air bottles and critical pressure plant systems.
Steam Systems: Primary steam piping networks, maneuvering valves, and bulkhead stop valves.
Safety Valves: Setting and lifting tests of boiler safety valves under steam.
3. Electrical and Automation Control Systems
Main & Emergency Switchboards: All high/medium-voltage electrical equipment, busbars, and generator circuit breakers.
Main Engine Controls: Governing systems and control mechanisms tied directly to critical Class Notations (such as UMS - Unattended Machinery Space, DP - Dynamic Positioning, or CCS).
4. Hull and Underwater Fittings
Sea Connections: All sea chests, shipside sea inlet valves, and overboard discharge valves (typically inspected during dry-dock or underwater surveys).
Engine Foundations: Holding down bolts and chocks.
5. Overriding Disqualifications (When the CE's Authority is Void)
Even for items normally acceptable for a Chief Engineer to survey (e.g., auxiliary pumps or air compressors), the Chief Engineer cannot carry out the inspection if:
Damaged Machinery: The component is known to have sustained any form of operational damage.
Temporary Repairs: The machinery has underwent temporary or provisional repairs.
Condition of Class (CoC): The item is subject to an outstanding Condition of Class or Statutory Memo.
MEO Class 1 Exam Tip
If the examiner asks "Why are these items excluded?", state that these components directly affect the structural integrity, primary redundancy, and core safety of the vessel. Class mandates a third-party, independent verification (Class Surveyor) to eliminate risk on single-point-of-failure machinery. Additionally, all items surveyed by you must face a Confirmatory Survey by the surveyor within a designated window (usually 3 to 5 months) to be officially credited.